Hi everyone

I needed a way to evaluate arbitrary JSON Path expressions, and I could not find any existing library that was fully complaint with RFC-9535. The two most popular libraries I found (ExJsonPath and Warpath) predate the RFC and, while sufficient for most common cases, they still contained some incompatible behavior, so I decided to implement a new one from scratch.

Introducing JSONPath, an RFC-9535 compliant JSON Path query evaluator.

Features

• Passes 100% of the JSONPath Compliance Test Suite.
• Supports all function extensions: length, count, match, search, value.
• No external dependencies.
• Does not support additional function extensions, for example sum, common in pre RFC9535 implementations.
• Does not support atom keys.

The only discrepancy with RFC9535 is regarding regular expressions. For match and search, the standard expects I-RegExp style expressions, while in JSONPath library any valid Elixir regular expression are accepted.

If you need any of the non-standarised functions/behaviors I would recommend to use any of the pre-RFC libraries. If you need to follow the standard as strictly as possible then consider giving JSONPath a try

Basic usage

document = [
      %{"name" => "Alice", "age" => 20},
      %{"name" => "Bob", "age" => 30},
      %{"name" => "Charlie", "age" => 25}
    ]
query = "$[?@.age < 27].name"
JSONPath.evaluate(document, query)
# {:ok, ["Alice", "Charlie"]}

Links

• Documentation: JSONPath — JSONPath v0.4.0
• Hex: json_path | Hex
• Code: